In a single year, an estimated 1.5 billion people travel by commercial airplane. So, it's not too difficult to imagine how easy it could be to become sick while in an airport or aboard an aircraft.  To keep the skies friendly to your health, consider following these ten travel-savvy tips:

1.  Wear loose clothing. If you feel bloated after disembarking from a plan, it’s because the low air pressure (8000 feet [2,438 meters] inside the jet cabin) makes our bodies swell up.
2.  Keep your fluids up. While in flight, drink 8 ounces (236 ml) of water during every hour. Cabin air is notoriously dry (0 to 2% humidity). Be sure to take the flight attendants up on their offers of bottled water during your flight.  Avoid tap water on airplanes. It is treated with mild detergents, and no regulatory standards are in effect for commercial aircraft water tanks.
3.  Sip smart. Avoid alcohol and caffeinated beverages — which act as diuretics. Alcohol’s intoxication effect also is more pronounced when consumed in the rarefied atmosphere of air travel.
4.  Skip the airline food. Snacks are loaded with salt. Airline meals are typically high in fat and preservatives. Brown bag something to tide you over until you reach your destination.
5.  Wiggle a little. While seated do some isometric exercises (contract and relax muscles from head to toe). Stand up at your seat to help reduce swelling in the legs and feet. Walk the length of the plane at least once during the flight.
6.  Grab some ZZZs. To maximize your chances of falling, and staying, asleep on the flight, you might want to bring a few supplies: earplugs, eye mask, neck pillow, sweater, and cotton socks.
7.  Speak up. Clammy skin, impaired vision, and difficulty concentrating may be a result of a lack of fresh, oxygenated air being supplied to the cabin. A lack of air results in lack of oxygen to the brain, a medical condition called “hypoxia,” which may trigger dizziness, headaches, chest pain, nausea, fatigue, and other unpleasant effects. Newer jets have been designed with less fresh air capacity for passengers; but most of us can attest to having difficulty with the quality or quantity of air on most flights we’ve endured. Passengers can ask for “air packs” to be turned on and “recirculation fans” to be turned off. It is standard operating procedure for pilots to turn off 30% of the air supply until a passenger complains, since it costs $80/hour for a 747 to run a single air pack.
8.  Humidify yourself. At check-in, mist your nasal passages, then put the spray away into your checked luggage.
9.  Grease up. At check-in, coat the inside of your nostrils with edible oil (corn, olive, jojoba, almond, or similar) to help block the spread of airborne germs (then put the oil away into your checked luggage). Avoid petroleum-based products and synthetic chemicals.
10. Submerge yourself upon arrival. After landing, dive into a pool, ocean, lake, hot tub, or bath. Bathing when dehydrated will replenish moisture right through your pores. It will also relax and recharge you so you can enjoy your first outing of the trip.

Infection Protection, available from A4M, shares insights on how to avoid  germs in everyday settings.  Call to order (US tel: 773-528-4333), or visit the World Health Network Bookstore online at http://www.worldhealth.net.